Fix a few bugs passing arguments to RPC calls.
Fix a few bugs passing arguments to RPC calls.

jiawen/Halide,kgnk/Halide,kgnk/Halide,psuriana/Halide,psuriana/Halide,ronen/Halide,ronen/Halide,ronen/Halide,psuriana/Halide,kgnk/Halide,kgnk/Halide,kgnk/Halide,jiawen/Halide,jiawen/Halide,jiawen/Halide,psuriana/Halide,ronen/Halide,ronen/Halide,kgnk/Halide,ronen/Halide,psuriana/Halide,jiawen/Halide,psuriana/Halide,ronen/Halide,jiawen/Halide,psuriana/Halide,kgnk/Halide,jiawen/Halide,kgnk/Halide,ronen/Halide